JP2638939B2 - Sewing machine cloth feed controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to a cloth feed amount control device for a sewing machine.

(Prior art) As a conventional cloth feed amount control device of this kind of sewing machine,
Japanese Patent Application Laid-Open No. 61-103482 is known. One end of a lever operatively connected to the cloth feed adjuster is rotatable about a shaft, and the other end is connected to a solenoid core by a wire. Further, a protrusion protruding downward is formed near the center of the lever, and this protrusion can be engaged with a cam surface of a cam member connected to a stepping motor by rotation of the lever. I have. In this configuration, the stepping motor is operated to rotate the cam member, and the distance between the cam surface and the projection is changed to change the amount of rotation of the lever due to the excitation of the solenoid, thereby increasing or decreasing the amount of cloth feed. Set and adjust the cloth feed amount.

(Problems to be Solved by the Invention) However, in the above-described cloth feed amount control device, since the amount of increase or decrease of the cloth feed amount is set by the distance between the cam surface and the projection, the origin position is The setting is difficult based on the positional relationship between the surface and the projection. If the origin position is shifted once, it will not be possible to adjust the origin position accurately due to errors. There was a drawback that it shifted.

Therefore, an object of the present invention is to make it possible to easily adjust the origin and adjust the position to an accurate origin.

[Configuration of the invention]

(Means for Solving the Problems) The technical measures taken in the present invention to solve the above technical problems include a lever means rotatably mounted on a machine frame, and a lever means operatively connected to the lever means. A cloth feed adjuster coupled to increase and decrease the cloth feed amount according to the amount of rotation of the lever means,
An arm means rotatably mounted on the machine frame and having a tooth portion for rotating the lever means by engaging with the lever means, and transmitting the arm means via a transmission means; After starting the sewing machine and receiving the position detection signal of the lever means after the start of the sewing machine, the arm means is rotated by an angle corresponding to the position detection signal to position the lever means at a position just before contact with the arm means, and A driving means for receiving the cloth feed amount correction signal during driving and rotating the arm means by an angle corresponding to the correction signal, a detected part formed on the arm means, and an adjustable frame mounted on the machine frame. Detecting means for detecting the detected portion to set the origin position and detecting the amount of rotation of the arm means.

(Operation) The above technical means operates as follows. When the driving means is in the free state, the arm means is positioned at the position of the cloth feed amount "0", and the drive means is operated, whereby the arm means is rotated by a predetermined amount and positioned at the position where the cloth feed amount is the maximum. In this state, by sliding the detecting means, the detecting means is located at a position for detecting the detected portion, and thereby,
The origin position is adjusted. In this way, the origin can be adjusted only by sliding the detecting means at the position where the cloth feed amount is the maximum and adjusting the position to the position where the detected portion is detected, and the operation is extremely easy. In addition, the position can be adjusted to an accurate origin position with little error due to the adjustment.

Embodiment An embodiment of the present invention will be described with reference to the accompanying drawings.

A shaft 13 fixed in a casing 11 of the sewing machine 10 has a lever 13
Are rotatably supported. The lever 13 includes an extending portion 13a extending downward and a projecting portion 13b projecting in the lateral direction, and a pin 14 is implanted in the projecting portion 13b.
An upper end of a rod 15 is pivotally supported on this 14 so as to be relatively displaceable, and a pin 16 is implanted at a lower end of the rod 15. The right end of a link member 18 constituting a part of the cloth feed adjuster 17 is rotatably supported by the pin 16, and a pin 19 is implanted on the left end of the link member 18. ing. The lower end of a rod 22 operatively connected to a cam 21 eccentrically fixed to an upper shaft 20 is pivotally supported by the pin 19 in a rotatable manner. A spring 23 is provided between the rod 15 and the machine frame 11, and the lever 13 and the rod 15 are constantly urged in the counterclockwise direction by the urging force of the spring 23.

A stepping motor 25 is fixed to the machine casing 11 via a bracket 24. The axis of this stepping motor 25
A gear 28 is fixed to 25a, and this gear 28 has
A second arm 30 rotatably supported by a shaft 29 fixed to the machine frame 11 is engaged with the shaft 29. The shaft 29 has a second arm 30
A first arm 31 that pivots integrally with the first arm 31 is pivotally supported, and a pin 32 that can be engaged with a side surface of the extending portion 13a of the lever 13 is implanted at the tip of the first arm 31.

An adjusting body 34 is screwed into the boss 11a of the machine casing 11. The adjustment body 34 is fixed by a screw 36 so as to rotate integrally with a knob 35 arranged outside the machine frame 11. Further, cam surfaces 13d, 13e and a concave portion 13c are formed on the side surface of the lever 13, and the cam surfaces 13d, 13e and the concave portion 13c can be brought into contact with the distal end portion 34a of the adjusting body 34, respectively. . In this configuration, when the user rotates the knob 35, the adjusting body 34 is rotated.
Is moved on the cam surface 13d with respect to the machine frame 11, whereby the lever 13 is rotated to set the cloth feed amount.

On the bracket 24, a sensor bracket 37 is slidably held by a pin 38 via an elongated hole 39 formed in the sensor bracket 37. A sensor 41 for detecting the projection 40, which is a detection target, formed on the second arm 30 is fixed to the sensor bracket 37. The position at which the sensor 41 detects the projection 40 is the origin position (solid line in the drawing). The position where the sensor 41 has detected the protrusion 40 can be known by means such as a buzzer (not shown).

In the above-described configuration, when the user rotates the knob 35 by an amount corresponding to a desired feed amount, the adjusting body 34 slides, and the sliding of the adjusting body 34 causes the distal end portion 34a to press while sliding on the cam surface 13d. Then, the lever 13 rotates clockwise in the figure by the amount of the pressing. As a result, the lever 13 is at the position indicated by the dashed line in the figure. As a result, the rod 15 slides downward in the figure, moves the position of the pin 16 which is the center of swing of the link member 18, and changes the rotation range of the link member 18, thereby setting a desired cloth feed amount. You. In this state, when the sewing machine 10 is operated, the cam 21 rotates with the rotation of the upper shaft 20, that is, the vertical movement of the sewing needle (not shown), and the rod 22 is moved up and down. By rotating the link member 17 clockwise in the figure in synchronization with the upward sliding of the rod 22, that is, the upward movement of the sewing needle, the cloth feed adjuster 18 is operated, and the feed dog is moved by a predetermined feed amount. Rotate the cloth and feed the cloth. Along with the operation of the sewing machine 10, the stepping motor 32 operates to rotate the first arm 31 and the second arm 30 by a predetermined angle from the origin position (the position indicated by the solid line in the drawing). The rotation of the first arm 31 and the second arm 30 is performed by a signal from a potion (not shown) for detecting the position of the lever 13 until the pin 32 comes close to the extended portion 13a of the lever 13 in the drawing. It is up to the position of the dashed line. The sewing is performed at the cloth feed amount described above, and a stepping motor 32 is operated by a signal from a cloth end detector (not shown) while the sewing machine 10 is operating, and the first arm 31 and the second arm 30 are moved to two points shown in the drawing. It rotates to the position of the chain line. The rotation of the first arm 31 and the second arm 30 causes the pin 32 to engage with and push the extending portion 13a, thereby rotating the lever 13 clockwise to the position indicated by the two-dot chain line in the drawing. This causes the rod 15 to slide downward and pin
16 moves, and the cloth feed amount gradually changes gradually as the sewing is performed. When sewing is completed and the operation of sewing machine 10 stops,
The stepping motor 25 rotates in the opposite direction to the rotation described above,
The lever 13 returns to the origin position, that is, the position shown by the solid line, and the lever 13 is returned by the urging force of the spring 23 until the cam surface 13d comes into contact with the distal end portion 34a, that is, to the position shown by the one-dot chain line. Become.

 Next, the origin adjustment will be described.

By rotating the knob 35, the lever 13 is rotated to the position of the cloth feed amount "0", that is, the position of the two-dot chain line in the figure, while watching the cloth feed amount displayed outside (not shown).
In this state, the first arm 30 and the first arm 31 are rotated to a position where the pin 32 and the extending portion 13a engage, and the first arm 30 and the first arm 31 are rotated.
The arm 31 and the second arm 30 are also at the position of the cloth feed amount “0”. From this position, the stepping motor 25 is operated,
The first arm 31 and the second arm 30 are rotated by a certain amount until the cloth feed amount reaches the maximum position. In this state, the position of the sensor 41 is adjusted by sliding the bracket 37 so that the sensor 41 detects the protrusion 41. This state, that is, the position where the first arm 31 and the second arm 30 are at the positions where the cloth feed amount is the maximum is the origin position. As described above, when adjusting the origin, the sensor 41 is projected at the position where the cloth feed amount is the maximum.
Can be adjusted only by adjusting to the position where the is detected, and the operation is extremely easy.

Further, by repeatedly performing the above operation, an accurate origin position can be obtained.

〔The invention's effect〕

A lever means rotatably mounted on the machine frame; a cloth feed adjuster operatively connected to the lever means for increasing and decreasing the cloth feed amount in accordance with the amount of rotation of the lever means; An arm means which is movably mounted and has a toothed portion and which is engaged with the lever means by rotating the lever means to rotate the lever means; and In response to the position detection signal of the lever means, the arm means is rotated by an angle corresponding to the position detection signal to position the lever means at a position immediately before contact with the arm means, and the cloth feed amount during driving of the sewing machine. A driving unit that receives the correction signal and rotates the arm unit by an angle corresponding to the correction signal, a detection unit formed on the arm unit, and the detection unit that is mounted on the machine frame so as to be adjustable. Detect and set the origin position And the detecting means for detecting the amount of rotation of the arm means constitutes the cloth feed control device of the sewing machine, so that the origin adjustment is performed by sliding the detecting means at the position where the cloth feed amount is the maximum to move the detected portion. Adjustment to the position to be detected can be performed with simple operation only by simple operation, and furthermore, it can be adjusted to an accurate origin position with few errors.

[Brief description of the drawings]

 The figure is a sectional view of the sewing machine according to the present invention. 11 ... machine frame, 13 ... lever (lever means), 17 ... cloth feed adjuster, 25 ... stepping motor (drive means), 28 ... gear (transmission means), 30 ... 1st arm ( Arm means), 31 second arm (arm means), 40 projection (measured means), 41 sensor (detecting means).

Claims (1)

(57) [Claims] 1. A lever means rotatably mounted on a machine frame, a cloth feed adjuster operatively connected to the lever means for increasing and decreasing the cloth feed amount in accordance with the amount of rotation of the lever means. An arm means rotatably mounted on the machine frame and having a tooth portion for rotating the lever means by engaging with the lever means, and transmitting the arm means via a transmission means; After starting the sewing machine and receiving the position detection signal of the lever means after the start of the sewing machine, the arm means is rotated by an angle corresponding to the position detection signal to position the lever means at a position just before contact with the arm means, and A driving means for receiving the cloth feed amount correction signal during driving and rotating the arm means by an angle corresponding to the correction signal, a detected part formed on the arm means, and an adjustable frame mounted on the machine frame. Detecting the detected part The cloth feed control device of the sewing machine and a detection means for detecting the amount of rotation of the set and the arm means the point position.